A digital hydraulic intelligent control system and excavator

Abstract

The present application discloses a digital hydraulic intelligent control system and an excavator. The intelligent control system includes a power source, a hydraulic medium source, a pumping unit, a first control valve, a second control valve, a hydraulic actuator and an electronic control system. The first control valve is provided with a supply medium chamber and a return medium chamber, a supply medium inlet channel and a supply medium outlet channel, a return medium inlet channel and a return medium outlet channel, and a supply and flow cut-off control switch. The supply and flow cut-off control switch controls the opening and closing of the supply medium outlet channel. The supply and flow cut-off control switch is driven by a driving unit. The power source and the pumping unit are arranged in a transmission manner. The pumping unit pumps hydraulic medium to the supply medium chamber. The outlet end of the supply medium outlet channel and the inlet end of the return medium inlet channel are respectively connected to the corresponding oil port of the second control valve through a one-way oil circuit. The outlet end of the return medium outlet channel is connected to the hydraulic medium source. The intelligent control system can realize a linear correspondence between the fluid power unit and the electronic pulse signal.

Description

Technical Field

[0001] The present application belongs to the field of fluid transmission technology, in particular to the field of hydraulic transmission technology, and particularly relates to a digital hydraulic intelligent control system and an excavator. Background Art

[0002] Fluid transmission technology is widely used in all walks of life. It is especially widely used in the field of engineering machinery. Engineering machinery has the advantages of high work efficiency and strong operating capacity and is widely used. Although the existing engineering machinery can meet the requirements of most projects, most of the existing engineering machinery requires operators to operate on-site to implement related operations. In some special working conditions and high-risk applications, it may even pose a great threat to the life of the operator. Due to the nonlinear relationship between the flow and pressure at the throttle of the control valve in the existing hydraulic system, it is difficult to establish a linear correspondence between the flow or pressure and the modern electronic control pulse signal, so it is difficult to achieve intelligent control through the control program of the chip. At most, remote simulation control of specific personnel can be achieved through remote sensing technology. Conventional remote control or automatic driving technology usually uses electrical components such as stepper motors that are easy to digitally control to achieve drive, but the power density of electrical components such as stepper motors is relatively small compared to hydraulic technology, and it is difficult to meet the working conditions of high power density in a small space (for example, construction rescue, etc.). Therefore, digital hydraulics that connect hydraulic technology with high power density with digitally controlled electrical components have become a development direction.

[0003] There are currently two views on digital hydraulics in the industry: one is to discretize the flow in the hydraulic system into a controllable digital quantity through a high-speed switching valve to facilitate digital control; the other is to control the main parameters of hydraulic components through digital electrical control, which is called digital hydraulics. Due to the limitations of high-speed switching valve technology, these two hydraulic digital technologies are difficult to meet the needs of high-power engineering hydraulic technology; the other is difficult to adjust the accuracy of pressure or flow control in real time due to the large changes in the temperature or density of the working medium. Although our company has developed sensors such as "a pipe joint for composite detection of hydraulic multi-parameters (hydraulic pressure, temperature, pressure pulsation, flow meter flow pulsation)", real-time data collection can be performed on the pressure p and flow q of the inlet and outlet of hydraulic functional components (hydraulic pumps, hydraulic cylinders, hydraulic motors), so that the power p·q of the inlet and outlet of the hydraulic components can be grasped in time, thereby providing "eyes" for the hydraulic system of AI intelligent control. However, an intelligent control system needs to achieve autonomous control and autonomous health management. Although eyes have improved the level of autonomous health management, eyes alone are not enough, and the execution unit also needs to meet the requirements of precision and controllability. Taking excavators as an example, there are two main types of hydraulic actuators for hydraulic excavators: one is the hydraulic cylinder, and the other is the hydraulic motor. Since the load ports of the hydraulic actuators of traditional hydraulic excavators are not independently controlled, the pressure p or flow q between the load ports of each hydraulic actuator interferes with each other, making it difficult to quantify the control; due to the large number of hydraulic control valves used, the throttle opening of the control valve position generally has no linear relationship with the actual flow or pressure, making it difficult to establish a corresponding relationship with today's discrete electronic and electrical control signals, which in turn makes it difficult to use the digital signals in the existing programming, big data and network intelligent control systems to perform digital and precise control of hydraulic excavators.

[0004] In addition, in the prior art, the hydraulic actuator (especially the hydraulic cylinder) needs to squeeze the hydraulic medium on the non-working side out of its interior. Due to the obstruction of the throttle and the pipeline components, there is back pressure in the extruded part. The power generated by this back pressure is, in most cases, an invalid or harmful power consumption that hinders the normal work of the hydraulic actuator, and is an invalid power that causes the hydraulic medium to heat up. Under another working condition where the load inertia or gravity works, the hydraulic actuator (especially the hydraulic cylinder) needs to generate back pressure on the hydraulic medium on the non-working side to buffer the load inertia or gravity. The traditional method is to achieve slow operation of the hydraulic actuator in the form of throttling, which will inevitably cause the heat loss of this throttling to pollute the hydraulic system, causing power loss due to forced heat dissipation caused by excessive oil temperature in the hydraulic system. Therefore, methods to reduce invalid power loss or increase hydraulic power recovery have also become a research hotspot for energy conservation and environmental protection.

[0005] Therefore, there is an urgent need to invent a method and means for discretizing the power flow of hydraulic fluid, and with the help of feedback from real-time flow and pressure detection technology, so as to realize an intelligent hydraulic system with autonomous control and autonomous health management, which can be used for intelligent control of hydraulic systems of engineering machinery such as excavators for remote disaster rescue. To this end, the applicant proposed a hydraulic excavator and intelligent control system with digital oil supply from the perspective of establishing a linear connection between electronic and electrical and the discretization of hydraulic fluid power flow, and solved the problem of invalid back pressure power consumption of hydraulic actuators or excessive oil temperature caused by excessive throttling losses in the hydraulic system through a high-speed pump source, multi-way valve, reversing valve and control system that are different from conventional ones.

[0006] It should be noted that the above contents belong to the technical knowledge of the inventor and do not necessarily constitute prior art. Summary of the invention

[0007] The present invention provides a digital hydraulic intelligent control system to solve at least one of the above technical problems.

[0008] A digital hydraulic intelligent control system includes a power source, a hydraulic medium source, a pumping unit, a first control valve, a second control valve, a hydraulic actuator and an electronic control system; the first control valve includes a first valve body, a supply medium chamber and a return medium chamber are provided inside the first valve body, a supply medium inlet channel and a supply medium outlet channel connected to the supply medium chamber are provided on the first valve body, and a return medium inlet channel and a return medium outlet channel connected to the return medium chamber are provided on the first valve body; the first control valve also includes a supply flow cut-off control switch and a return flow cut-off control switch, the supply flow cut-off control switch controls the opening and closing of the supply medium outlet channel, the return flow cut-off control switch controls the opening and closing of the return medium inlet channel, and the supply flow cut-off control switch and the return flow cut-off control switch are driven by a driving unit; the power source is arranged in a transmission with the pumping unit, the hydraulic medium inlet of the pumping unit is connected with the hydraulic medium source, and the hydraulic medium outlet of the pumping unit is connected with the inlet end of the supply medium inlet channel, so as to provide hydraulic medium to the supply medium chamber ; The outlet end of the flow medium discharge channel and the inlet end of the return medium inlet channel are respectively connected to the corresponding oil port of the second control valve through a one-way oil circuit, and the outlet end of the return medium discharge channel is connected to the hydraulic medium source to form a working circuit; the second control valve is driven by a driving device; the second control valve is respectively connected to the first load port and the second load port fluid circuit of the hydraulic actuator, so that the second control valve can perform reversing and / or speed control on the hydraulic actuator; or, the second control valve is connected to the first load port fluid circuit of the hydraulic actuator, so that the second control valve can perform reversing and / or speed control on the hydraulic actuator; the drive unit and the drive device are both connected to the electronic control system, and the drive unit and the drive device are both controlled by the electronic control system; when working, the flow on-off control switch is driven by the drive unit to make the flow medium discharge channel continuously in an alternating working state of being connected and closed, and to make the first control valve supply pulse hydraulic medium to the outside, and the drive unit controls the frequency of connecting the flow medium discharge channel.

[0009] It is further selectively selected that the first valve body of the first control valve is provided with more than two supply medium cavities and at least one return medium cavity, each supply medium cavity and one return medium cavity are adaptably connected and serve as components of the same flow path; each supply medium cavity is respectively connected to the corresponding oil port of the second control valve through one or more supply medium discharge channels through a one-way oil circuit, and the outlet end of the return medium discharge channel is connected to the hydraulic medium source through a one-way oil circuit to form a working circuit; and the supply flow cut-off control switch is provided in each supply medium discharge channel, and each supply flow cut-off control switch is driven by a drive unit; and the drive unit is further selectively selected to be a servo motor, a stepper motor or a variable frequency motor, and / or the drive device is configured to be a servo motor or a stepper motor.

[0010] The digital hydraulic intelligent control system is further selectively selected to include a negative pressure generating device, and the reflux medium chambers arranged on the first valve body of the first control valve are respectively connected to the negative pressure generating devices. When the negative pressure generating device is in a working condition of forming negative pressure, the hydraulic medium in the reflux medium chamber connected to the negative pressure generating device is sucked out.

[0011] When the first control valve has a reflux medium chamber:

[0012] The negative pressure generating device is further selectively selected to be a cylinder piston mechanism, the cylinder piston mechanism includes a cylinder and a piston, the piston and the cylinder form a first volume chamber with a variable volume, the cylinder is provided with a first medium inlet and a first medium outlet connected to the first volume chamber; the reflux medium volume chamber is connected to the first volume chamber via a first switch unit and the first medium inlet, and when the volume of the first volume chamber increases, the first switch unit is in an open state; during the operation of the cylinder piston mechanism, the cylinder piston mechanism sucks the hydraulic medium in the reflux medium volume chamber into the first volume chamber, and squeezes the hydraulic medium sucked into the first volume chamber from the first medium outlet to the hydraulic medium source;

[0013] When the first control valve has a plurality of reflux medium cavities:

[0014] The negative pressure generating device is selectively configured as a cylinder piston mechanism, the cylinder piston mechanism includes a cylinder and a piston, the piston and the cylinder form a first volume chamber and a second volume chamber with variable volumes, the cylinder is provided with a first medium inlet and a first medium outlet communicating with the first volume chamber, and a second medium inlet and a second medium outlet communicating with the second volume chamber; each of the partial reflux medium volumes are communicated with the first volume chamber through a reflux medium discharge channel and a first medium inlet, and each of the remaining partial reflux medium volumes are communicated with the second volume chamber through a reflux medium discharge channel and a second medium inlet, a first switch unit is provided on each reflux medium discharge channel, and the reflux medium volume chamber communicating with the first volume chamber is communicated with at least one of the reflux medium volume chambers communicating with the second volume chamber through a third switch unit; a second switch unit is provided on a fluid channel at or downstream of the first medium outlet and a fluid channel at or downstream of the second medium outlet; when the volume of the first volume chamber increases, the reflux medium in the working flow path and connected to the first volume chamber is The first switch unit on the discharge channel is in an open state, and the second switch unit connected to the first cavity is in an off state; when the volume of the first cavity decreases, the first switch unit on the return medium discharge channel on the working flow path and connected to the first cavity is in an off state, and the second switch unit connected to the first cavity is in an open state; when the volume of the second cavity increases, the first switch unit on the return medium discharge channel on the working flow path and connected to the second cavity is in an open state, and the second switch unit connected to the second cavity is in an off state; when the volume of the second cavity decreases, the first switch unit on the return medium discharge channel on the working flow path and connected to the second cavity is in an off state, and the second switch unit connected to the second cavity is in an open state; when the pressure difference in the return medium cavity connected to the third switch unit is below a set value, the third switch unit is in an off state, and when the pressure difference in the return medium cavity connected to the third switch unit is above a set value, the third switch unit is in an on state.

[0015] It is further selectively selected that the first control valve also includes an energy storage unit, the energy storage unit is connected to the supply medium chamber so that the supply medium chamber is within a set pressure range, the supply medium chamber and the return medium chamber in the same flow path are connected via a one-way control switch with a set opening pressure, and when the pressure in the supply medium chamber is greater than the set opening pressure, the supply medium chamber and the return medium chamber are in a connected state; or, selectively, the first control valve also includes an energy storage unit, the energy storage unit is connected to the supply medium chamber so that the supply medium chamber is within a set pressure range, the supply medium chamber and the return medium chamber are connected via an electromagnetic proportional overflow valve with an adjustable opening pressure, and when the pressure in the supply medium chamber is greater than the set opening pressure, the supply medium chamber and the return medium chamber are in a connected state.

[0016] The second control valve is further selectively selected to be a reversing valve; or, the second control valve is selectively made to include two second valve bodies, one of which is connected to a load port of a hydraulic actuator, and the other of which is connected to another load port of the hydraulic actuator, each of which is provided with a first fluid channel, a second fluid channel and a third fluid channel, and the second valve body is also provided with a first control switch for controlling the on-off of the first fluid channel, a second control switch for controlling the on-off of the second fluid channel and a third control switch for controlling the on-off of the third fluid channel; when one of the first fluid channel, the second fluid channel and the third fluid channel is in an on state, the other two are in an off state; when the first fluid channel is in an on state, the second control valve is in a working state of supplying fluid medium to the hydraulic actuator; when the second fluid channel is in an on state, the second control valve is in a working state of refluxing the fluid medium; when the third fluid channel is in an on state, the second control valve is in a working state of replenishing fluid medium to the hydraulic actuator.

[0017] When the second control valve includes the second valve body, the first control switch, the second control switch and the third control switch are further selectively driven by different driving devices, and each driving device is controlled by the electric control system so that the first control switch, the second control switch and the third control switch each complete an independent open state or closed state; or, the first control switch is selectively made to include a first rotor valve core having a first fluid channel, the second control switch includes a second rotor valve core having a second fluid channel, and the third control switch includes a third rotor valve core having a third fluid channel, a valve core cavity adapted to the first rotor valve core, the second rotor valve core and the third rotor valve core is provided in the second valve body, the first rotor valve core, the second rotor valve core and the third rotor valve core are coaxially arranged and driven by the same driving device, the driving devices are all connected to the electric control system, and the driving unit and the driving device are all controlled by the electric control system; the driving device controls the open state or closed state of the first control switch, the second control switch and the third control switch.

[0018] The pumping unit is further selectively made to include at least one cylinder-piston unit, the cylinder-piston unit includes a piston cylinder and a piston matched with the piston cylinder, a piston rod is fixedly provided at one end of the piston, the piston rod is connected to the crankshaft through a connecting rod, and during the rotation of the crankshaft, the piston reciprocates relative to the piston cylinder; a barrier body is provided inside the piston cylinder that is tightly connected to the inner circumference of the piston cylinder, one end of the piston rod is connected to the connecting rod through the barrier body, and the piston, the piston cylinder and the barrier body form a medium chamber with a variable volume; the pumping unit also includes a medium inlet channel and a medium discharge channel connected to the medium chamber; during operation, the hydraulic medium provided by the medium source can enter the medium chamber unidirectionally through the medium inlet channel, and during the movement of the piston toward the barrier body, at least part of the hydraulic medium in the medium chamber is discharged unidirectionally from the medium discharge channel.

[0019] The electronic control system is further selectively selected to include an intelligent control module and a sensor group, wherein the sensor group includes multiple sensor units for detecting parameter information of the pumping unit, the first control valve, the second control valve and the hydraulic actuator, and the multiple sensor units are connected to the intelligent control module of the electronic control system to collect and provide monitoring information for the electronic control system; when working, the intelligent control module obtains the detection information of the pumping unit, the first control valve, the second control valve and the hydraulic actuator from the sensor group and makes a judgment, and then controls the power source, the pumping unit, the first control valve and the second control valve according to the set program.

[0020] The present application also discloses an excavator using the digital hydraulic intelligent control system described in any of the above solutions,

[0021] The power source is set as an engine, an electric motor or a hybrid power drive unit including an engine and an electric motor; the hydraulic actuator of the excavator includes a travel motor, a rotary motor and a plurality of variable-length telescopic cylinders; two supply medium cavities and two return medium cavities are arranged on the first valve body of the first control valve; one of the supply medium cavities is adapted to one return medium cavity and serves as a component of the same flow path, and the other supply medium cavity is adapted to the other return medium cavity and serves as a component of the same flow path; wherein, one of the supply medium cavities is connected to a travel motor and a return medium cavity through a supply medium discharge channel. The sensor group comprises: a sensor for monitoring the flow rate, pressure and pressure pulsation signal of the hydraulic medium inlet and the hydraulic medium outlet of the pumping unit; a sensor for monitoring the flow rate, pressure and pressure pulsation signal of at least part of the medium channel of the first control valve; a sensor for monitoring the flow rate, pressure, pressure pulsation signal and angular displacement of the load port of the hydraulic motor; and a sensor for monitoring the flow rate, pressure, pressure pulsation signal and angular displacement of the shaft end of the load port of the telescopic cylinder.

[0022] In the present application, those skilled in the art are motivated to set necessary components, units or systems at necessary places according to the known technologies in the relevant fields.

[0023] The digital hydraulic intelligent control system proposed in this application can bring the following beneficial effects:

[0024] 1. The first control valve of the present application can discretize and measurably divide the hydraulic medium, realize the digitization and intelligence of the control system, and thus provide technical guarantee and technical basis for the intelligent control of the control system; further with the help of the development of software development, digital simulation, cloud computing, etc., the intelligent and autonomous control of the excavator of the hydraulic control system can be realized.

[0025] 2. The present application sets up a negative pressure generating device, under the suction action of the negative pressure generating device, the hydraulic medium in the reflux medium chamber can be sucked out, and at the same time, the non-working chamber of the hydraulic actuator (especially the hydraulic cylinder) connected to the reflux medium chamber forms a negative pressure working condition, thereby reducing the ineffective power consumption of the back pressure and achieving better energy-saving effect.

[0026] 3. The pumping unit of the present application realizes high-speed reciprocating motion of the piston in the piston cylinder by connecting the piston of the cylinder-piston unit to the crankshaft through a connecting rod, and utilizes the return stroke of the piston to push a large amount of fluid medium into the fluid channel, thereby overcoming the problem of self-priming difficulty when the existing fluid pumps are running at high speed; the fluid pump described in the present application comprises a variable-volume medium chamber formed by the piston, piston cylinder and barrier body, and during the reciprocating motion of the piston, the internal hydraulic medium entering the medium chamber is pumped to a specified position in the form of high speed and high pressure.

[0027] 4. The combination of the second control valve and the first control valve and the independent one-way oil circuit between the two of the present application can replace the existing multi-way valve, which can not only overcome the problems of mutual coupling and mutual interference of the oil supply pressures between the valves of the existing multi-way valve, but also truly realize the independent control of the load port of the hydraulic actuator; at the same time, by making the first control valve and the second control valve driven by a controlled motor (servo motor, stepper motor, etc.), the hydraulic control system can be digitized and discretized, thereby providing technical guarantee for the implementation of precise control and intelligent control.

[0028] 5. Since the present application enables the second control valve to independently control the two load ports of the hydraulic actuator by two independent control valve bodies, and utilizes the oil replenishment medium channel provided by the pressurized oil tank to prevent cavitation problems in the conversion from the negative pressure chamber to the high pressure chamber; utilizes the second control valve to be controlled by a controlled motor (servo motor, stepper motor, etc.) to drive the opening and closing frequency of the valve core fluid channel to realize the function of the hydraulic actuator's inching brake, thereby reducing the throttling heating problem caused by the existing one-way throttle valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0030] Figure 1 A schematic diagram of a digital hydraulic intelligent control system provided in an embodiment of the present application and including a fluid circuit, wherein the hydraulic actuator is a hydraulic cylinder;

[0031] Figure 2 A schematic diagram of a digital hydraulic intelligent control system provided in an embodiment of the present application, comprising a fluid circuit, wherein the hydraulic actuator is a hydraulic motor;

[0032] Figure 3 A schematic structural diagram of a first control valve provided in an embodiment of the present application, wherein the first control valve comprises two flow supply medium cavities and two return medium cavities;

[0033] Figure 4 A schematic structural diagram of an assembly formed by a first control valve and a negative pressure generating device provided in an embodiment of the present application, wherein the first control valve comprises a flow supply medium chamber and a return medium chamber;

[0034] Figure 5 A schematic diagram of the structure of an assembly formed by a first control valve, a negative pressure generating device and a hydraulic medium source provided in an embodiment of the present application, wherein the assembly includes two supply medium cavities and two return medium cavities;

[0035] Figure 6 for Figure 5 A partial enlarged view of the structure at A;

[0036] Figure 7 A schematic diagram of a control valve provided with a first control switch, a second control switch and a third control switch provided in an embodiment of the present application;

[0037] Figure 8 A schematic diagram of the structure of a control valve provided with a first control switch, a second control switch and a third control switch provided in an embodiment of the present application, wherein each of the control valves is connected to a load port of a hydraulic actuator, and two of the control valves can form one second control valve;

[0038] Fig. 9 for Figure 8 A schematic diagram of a projection of the first through hole, the second through hole and the third through hole on the valve core at one end of the valve core;

[0039] Fig.10 A schematic diagram of a second control valve formed by two control valves provided with a first control switch, a second control switch and a third control switch provided in an embodiment of the present application;

[0040] Fig.11 A schematic diagram of the structure of a pumping unit provided in an embodiment of the present application, wherein the pumping unit is in a first working state;

[0041] Fig.12 A schematic diagram of the structure of a pumping unit provided in an embodiment of the present application, wherein the pumping unit is in a second working state;

[0042] Fig.13 A schematic diagram of the structure of a pumping unit provided in an embodiment of the present application, wherein the pumping unit is in a second working state, and the piston and the piston cylinder form an oil containing chamber;

[0043] Fig.14 This is a schematic structural diagram of another pumping unit provided in an embodiment of the present application, and the pumping unit is in a first working state.

[0044] in,

[0045] 1 first control valve, 10 first valve body, 11 supply medium chamber, 12 reflux medium chamber, 13 supply medium inlet channel, 14 supply medium outlet channel, 15 reflux medium inlet channel, 16 reflux medium outlet channel, 17 supply flow cut-off control switch, 171 first rotary shaft valve core, 18 reflux flow cut-off control switch, 181 second rotary shaft valve core, 101 drive unit, 19 energy storage unit,

[0046] 2 second control valve, 20 second valve body, 21 first control switch, 211 first rotating body, 212 first through hole, 22 second control switch, 221 second rotating body, 222 second through hole, 23 third control switch, 231 third rotating body, 232 third through hole; 24 first fluid channel, 25 second fluid channel, 26 third fluid channel, 27 valve core, 281 fourth control switch, 282 fifth control switch, 283 sixth control switch, 284 seventh control switch, 285 driving device, 286 hydraulic actuator medium pipeline interface end,

[0047] 3 pumping unit, 31 cylinder piston unit, 311 piston cylinder, 312 piston, 313 piston rod, 314 connecting rod, 32 crankshaft, 33 barrier, 34 medium chamber of pumping unit, 35 medium inlet channel, 36 medium outlet channel, 37 medium source, 38 one-way control switch, 39 pressure regulating control switch, 30 oil chamber,

[0048] 4 negative pressure generating device, 41 cylinder body, 42 piston, 43 first chamber, 44 first medium inlet, 45 first medium outlet, 461 first switch unit, 462 second switch unit, 47 second chamber, 48 second medium inlet, 49 second medium outlet, 40 third switch unit, 401 first one-way switch, 402 second one-way switch,

[0049] 5 power source, 6 hydraulic medium source, 7 hydraulic actuator, 71 hydraulic cylinder, 72 hydraulic motor, 81 first load port, 82 second load port. DETAILED DESCRIPTION

[0050] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0051] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0053] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one scheme", "some schemes", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the scheme or example are included in at least one scheme or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same scheme or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more schemes or examples in a suitable manner.

[0055] For ease of description, "front", "rear", "left", "right", "up" and "down" in the following text refer to the positions of the control valve relative to the user when the control valve is in use.

[0056] In the present application, the so-called "supply medium chamber and return medium chamber as components of the same flow circuit" means that the supply medium chamber and the return medium chamber are both components of the same fluid circuit, that is, the supply medium chamber and the return medium chamber are connected to at least the same hydraulic actuator and serve as components of the same fluid circuit.

[0057] In the present application, "above a certain value" includes the number itself, for example, "above two" includes "two".

[0058] This application discloses a digital hydraulic intelligent control system, such as Figure 1 and Figure 2As shown, it includes a power source 5, a hydraulic medium source 6, a pumping unit 3, a first control valve 1, a second control valve 2, a hydraulic actuator 7 and an electronic control system; the first control valve 1 includes a first valve body 10, the first valve body 10 is provided with a supply medium cavity 11 and a return medium cavity 12, the first valve body 10 is provided with a supply medium inlet channel 13 and a supply medium outlet channel 14 connected to the supply medium cavity 11, the first valve body 10 is provided with a return medium inlet channel 15 connected to the return medium cavity 12 and a reflux medium discharge channel 16; the first control valve 1 also includes a supply flow cut-off control switch 17 and a reflux cut-off control switch 18, the supply flow cut-off control switch 17 controls the opening and closing of the supply flow medium discharge channel 14, and the reflux cut-off control switch 18 controls the opening and closing of the reflux medium entry channel 15, and the supply flow cut-off control switch 17 and the reflux cut-off control switch 18 are driven by the driving unit 101 respectively; the power source 5 is arranged in a transmission with the pumping unit 3, and the hydraulic medium inlet of the pumping unit 3 is connected to the The hydraulic medium source 6 is connected, and the hydraulic medium outlet of the pumping unit 3 is connected with the inlet end of the supply medium inlet channel 13 to provide hydraulic medium to the supply medium chamber 11; the outlet end of the supply medium discharge channel 14 and the inlet end of the return medium inlet channel 15 are respectively connected with the corresponding oil ports of the second control valve 2 through a one-way oil circuit, and the outlet end of the return medium discharge channel 16 is connected with the hydraulic medium source 6 to form a working circuit; the second control valve 2 is driven by a driving device 285; the second control valve 2 is respectively connected with the first load port 81 and the second load port 82 of the hydraulic actuator 7 by fluid circuits, so that the second control valve 2 can perform reversing and speed regulation (including braking) control on the hydraulic actuator 7; when working, the supply flow disconnection control switch 17 is driven by the driving unit 101 to make the supply medium discharge channel 14 continuously in an alternating working state of being connected and closed, and to make the first control valve 1 supply pulsed hydraulic medium to the outside, and the driving unit 101 controls the frequency of connecting the supply medium discharge channel 14. In the specific implementation, the power source 5 is not specifically limited, and it can be any device that can provide power, for example, the power source 5 is set to an engine, an electric motor, or a hybrid drive system including an engine and an electric motor. Figure 1 As shown, the hydraulic actuator 7 is set as a hydraulic telescopic cylinder; Figure 2 As shown, the hydraulic actuator 7 is configured as a hydraulic motor 72. In a specific implementation, the digital hydraulic intelligent control system can selectively include a plurality of hydraulic actuators 7, and each hydraulic actuator 7 can further refer to Figure 1 and Figure 2The connection mode shown forms multiple fluid circuits. It should be noted that the hydraulic medium source 6 is not specifically limited, and it can be any chamber that can provide hydraulic medium to the hydraulic intelligent control system. Specifically, the hydraulic medium source 6 can be selectively set as a hydraulic oil tank, and preferably the hydraulic oil tank is set as a booster oil tank whose internal pressure is greater than its external pressure. In specific implementation, a separation device capable of separating impurities can be further selectively set inside the booster oil tank. In order to maintain the booster oil tank within a set pressure range, an explosion-proof valve and a pressure-maintaining unit can be further selectively set on the booster oil tank. The present application provides a pressure-maintaining unit on the booster oil tank, so that the oil tank can be maintained within the set pressure range, and can effectively prevent dirt from entering the oil tank body and polluting the hydraulic medium. In specific implementation, a gas-liquid separation device is further selectively set inside or outside the booster oil tank, and the refluxed hydraulic medium flows through the gas-liquid separation device and is separated and stored in the booster oil tank, thereby ensuring that the bubbles released during negative pressure can be fully separated and / or dissolved from the hydraulic medium. In a specific implementation, the gas-liquid separation device is further selectively made to include a spiral gas-liquid separation channel or a vortex gas-liquid separation channel, and a separation hole is provided on the side wall of the spiral gas-liquid separation channel or the vortex gas-liquid separation channel, so that the gas in the refluxed hydraulic medium is separated under the action of centrifugal force, thereby reducing the influence of cavitation on the hydraulic system.

[0059] As a convertible embodiment, when the hydraulic actuator 7 only contains the first load port 81, in the specific implementation, the second control valve 2 is connected to the first load port 81 of the hydraulic actuator 7 in the fluid circuit, so that the second control valve 2 can perform switching control on the hydraulic actuator 7 by converting high pressure or low pressure, and can also perform speed control (including braking) by adjusting the opening size or rapid switching. This type of hydraulic actuator often includes a return spring so that this type of hydraulic actuator can also work reciprocatingly when a load port provides hydraulic medium.

[0060] As a convertible implementation, the first control valve 1 of the present application may selectively be provided with a (such as Figure 4 as shown) or a plurality of the flow medium chambers 11 (as shown Figure 3As shown), and further selectively make each of the supply medium cavities 11 selectively connected to one or more hydraulic actuators 7 (for example, a hydraulic motor 72, a hydraulic cylinder 71, etc.), the specific number of which can be selected and set according to the number of hydraulic actuators 7 provided in the hydraulic control system where the first control valve 1 is located, for example, make the first control valve 1 connected to one, two, three, four, five, six or more than seven hydraulic actuators 7; in specific implementation, the plurality of supply medium cavities 11 included in the first control valve 1 can be further selectively connected to one or more of the hydraulic actuators 7. As a convertible embodiment, the first control valve 1 can selectively set more than two supply medium cavities 11 and more than one return medium cavities 12 on the first valve body 10; in addition, in specific implementation, the first control valve 1 including one supply medium cavity 11 and one return medium cavity 12 can also be selectively used as a control valve unit, and more than two of the first control valve 1 units can be combined together as a multi-way valve of a hydraulic control system according to actual needs. The first control valve 1 of the present application is respectively provided with control switches on the flow medium discharge channel 14 and the return medium inlet channel 15, and is capable of individually controlling the opening and closing of the respective controlled channels, so that the first control valve 1 can provide hydraulic medium in a targeted manner according to the demand of the hydraulic actuator 7; at the same time, the oil circuits of the multiple hydraulic actuators 7 of the control system including the first control valve 1 can be supplied independently of each other, avoiding the problems of mutual coupling, mutual restriction, mutual influence, etc. existing in the traditional control system where the various hydraulic actuators 7 share the same pressure oil source, so that the oil source supply of the existing so-called load port independent control is also realized independently, overcoming the mutual interference problem of the shared oil circuit, and providing an effective technical basis for realizing the mutual independence, digitization and intelligent control of the sub-circuit units of the hydraulic control system.

[0061] As a preferred embodiment of the present application, the present application can further selectively provide more than two supply medium chambers 11 and at least one return medium chamber 12 inside the first valve body 10 of the first control valve 1, and each supply medium chamber 11 and one return medium chamber 12 are adaptably connected and serve as components of the same flow path; each supply medium chamber 11 is respectively connected to the first load port 81 of the hydraulic actuator 7 of the same number as the flow medium discharge channel through one or more supply medium discharge channels 14 through a one-way oil circuit, and the second load port 82 of the hydraulic actuator 7 is connected to the return medium chamber 12, and the supply flow interruption control switch 17 is provided in each supply medium discharge channel 14, and each supply flow interruption control switch 17 is driven by a drive unit 101. In specific implementation, the number of the supply medium cavities 11 and the number of the return medium cavities 12 can be selectively set on the first valve body 10 according to actual needs, and one return medium cavities 12 can be further selectively adapted to one or more supply medium cavities 11, that is, one return medium cavities 12 can be selectively used as a component of the same flow path as one supply medium cavities 11, or one return medium cavities 12 can be selectively adapted to multiple supply medium cavities 11. Figure 3 As shown, two flow supply medium cavities 11 and two return medium cavities 12 are provided inside the first valve body 10 of the first control valve 1 .

[0062] The aforementioned embodiments of the present application and their variant embodiments are implemented in detail. Figure 4 and Figure 5 The first control valve 1 shown in the figure can further selectively enable the supply flow cut-off control switch 17 for controlling the opening and closing of the supply medium discharge channel 14 and the return flow cut-off control switch 18 for controlling the opening and closing of the return medium inlet channel 15 to be driven by independent drive units 101 respectively, or as Figure 3 As shown, in a specific implementation, the supply flow cut-off control switch 17 for controlling the opening and closing of the supply flow medium discharge channel 14 and the reflux flow cut-off control switch 18 for controlling the opening and closing of the reflux medium inlet channel 15 as components of the same flow path can also be selectively driven by the same driving unit 101.

[0063] As a preferred embodiment of the present application, the first valve body 10 is further selectively provided with two supply medium chambers 11 and two return medium chambers 12, wherein one supply medium chamber 11 is adapted to one return medium chamber 12 and serves as a component of the same flow path, and another supply medium chamber 11 is adapted to another return medium chamber 12 and serves as a component of the same flow path; each supply medium chamber 11 is connected to a supply medium discharge channel 14, and each return medium chamber 12 is connected to a return medium inlet channel 15; as a convertible embodiment, the present application can also selectively connect each supply medium chamber 11 to more than two supply medium discharge channels 14, that is, the supply medium chamber 11 can provide hydraulic medium to more than two hydraulic actuators 7; each return medium chamber 12 is connected to more than one return medium inlet channel 15.

[0064] As a convertible implementation, it is also possible to selectively, during operation, the flow cut-off control switch 17 makes the flow medium discharge channel 14 continuously in an alternating working state of being on and off, so that the control valve supplies pulsed hydraulic medium to the outside. The present application enables the flow cut-off control switch 17 to be frequently in an open or closed state under the drive of the drive unit 101, thereby enabling the control valve to provide pulsed hydraulic medium to the hydraulic actuator 7, and to implement a measurable and split supply of the hydraulic medium, so that the hydraulic medium supply can be discrete and digitalized, so that it can be combined with the electronic control technology to provide technical support for the intelligent control of the fluid control system using the control valve.

[0065] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application and their convertible embodiments can further selectively set the driving unit 101 as a driving motor, and the flow cut-off control switch 17 is set as a first rotating shaft valve core 171 with a first channel. When working, the first rotating shaft valve core 171 is driven by the driving motor and rotates according to the set angle and speed. When the first rotating shaft valve core 171 rotates to the set angle range, the first channel makes the flow medium discharge channel 14 controlled by it in a connected state; in specific implementation, the first rotating shaft valve core 171 is further selectively set as a rotating shaft, and the first channel is set as a through hole running through the rotating shaft. The reflux cut-off control switch 18 is further selectively set as a second shaft valve core 181 with a second channel. When working, the second shaft valve core 181 is driven by a driving motor and rotates at a set speed. When the second shaft valve core 181 rotates to a set angle range, the second channel makes the reflux medium entering the channel 15 controlled by it be in a connected state. In specific implementation, the second shaft valve core 181 is further selectively set as a shaft, and the second channel is also set as a through hole that penetrates the shaft. As a convertible embodiment, the first shaft valve core 171 of the supply cut-off control switch 17 and the second shaft valve core 181 of the reflux cut-off control switch 18 in the same flow path can be further selectively set coaxially and driven by the same driving motor; or, the first shaft valve core 171 of the supply cut-off control switch 17 and the second shaft valve core 181 of the reflux cut-off control switch 18 in the same flow path can be selectively set non-associatedly and driven by different driving motors respectively.

[0066] As a preferred embodiment of the present application, all of the aforementioned embodiments containing the drive motor can further selectively enable the drive motor to be set as a servo motor, a stepper motor or a variable frequency motor, and the drive motor is electronically connected to the electronic control unit to control the frequency of the supply flow interruption control switch 17 connecting the supply flow medium discharge channel 14 and to control the frequency of the return flow interruption control switch 18 connecting the return flow medium into the channel 15.

[0067] As a convertible embodiment, it is also possible to selectively, during operation, the flow cut-off control switch 17 causes the flow medium discharge channel 14 to be continuously in an alternating working state of being on and off, so that the control valve supplies pulsed hydraulic medium to the outside. The present application enables the flow cut-off control switch 17 to be frequently in an open or closed state under the drive of the drive unit 101, thereby enabling the control valve to provide the hydraulic actuator 7 with a pulsed hydraulic medium with a relatively stable pressure P, ensuring that the hydraulic medium temperature T of each pulse is relatively constant, the density ρ is relatively constant, and the volume ΔV is approximately equal, thereby implementing a measurable and divisible supply of the hydraulic medium. In this way, the energy of the hydraulic medium supply can be discretized into a hydraulic medium pulse unit ΔVP, so that it forms a one-to-one linear relationship with the frequency f of the flow cut-off control switch 17 connecting the flow medium discharge channel 14, and then through the flow cut-off control switch 17, the hydraulic medium discharge channel 14 is connected to the hydraulic medium discharge channel 14. The frequency f at which the off control switch 17 connects the flow medium discharge channel 14 forms a one-to-one linear relationship with the frequency at which the drive unit 101 rotates one circle, and then the digital electric pulse signal controlling the drive unit 101 forms a linear correspondence with the hydraulic medium pulse energy unit ΔVP, that is, the number of electronic pulses ne controlled by the program in the intelligent control unit within a certain period of time Δt forms a linear correspondence with the number of pulses nh=fΔt of the pulse energy unit ΔVP controlling the hydraulic actuator 7, thereby providing technical support for the digitalization and intelligent control of the fluid control system of the control valve using an electronic control system controlled by a computer or chip.

[0068] In specific implementation, since the rotation speed and rotation angle of the driving motor can be precisely controlled, the amount of hydraulic medium supplied by the flow medium chamber 11 can be indirectly and accurately calculated. By combining it with the control unit, the hydraulic medium can be accurately provided to the hydraulic actuator 7. By discretizing and digitizing the supply of hydraulic medium, intelligent control can be further realized.

[0069] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application and their convertible embodiments can further selectively make the digital hydraulic intelligent control system further include a negative pressure generating device 4, specifically as follows Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the reflux medium chamber 12 arranged on the first valve body 10 of the first control valve 1 is respectively connected to the negative pressure generating device 4. When the negative pressure generating device 4 is in a working condition of forming negative pressure, the hydraulic medium in the reflux medium chamber 12 connected to the negative pressure generating device 4 is sucked out.

[0070] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application containing the negative pressure generating device 4 can further selectively:

[0071] When the first control valve 1 has a return medium chamber 12:

[0072] The negative pressure generating device 4 is preferably configured as a cylinder piston mechanism, such as Figure 4 As shown, the cylinder-piston mechanism includes a cylinder 41 and a piston 42. The piston 42 and the cylinder 41 form a first volume chamber 43 with a variable volume. The cylinder 41 is provided with a first medium inlet 44 and a first medium outlet 45 that are connected to the first volume chamber 43. The reflux medium volume chamber 12 is connected to the first volume chamber 43 via a first switch unit 461 and the first medium inlet 44. When the volume of the first volume chamber 43 increases, the first switch unit 461 is in an open state, or when the pressure in the first volume chamber 43 is lower than the pressure in the reflux medium volume chamber 12 to a set value, the first switch unit 461 is in an open state. During the operation of the cylinder-piston mechanism, the cylinder-piston mechanism sucks the hydraulic medium in the reflux medium volume chamber 12 into the first volume chamber 12. cavity 43, and squeezes the hydraulic medium sucked into the first cavity 43 from the first medium outlet 45 to the hydraulic medium source 6; during the process of the cylinder piston mechanism stopping working, when the pressure of the hydraulic medium in the reflux medium cavity 12 is greater than the pressure in the first cavity 43 to a set value, the first switch unit 461 is in an open state, and the hydraulic medium in the reflux medium cavity 12 enters the first cavity 43 through the first switch unit 461; when the pressure of the hydraulic medium in the first cavity 43 is greater than the pressure of the hydraulic medium source 6 to a set value, the second switch unit 462 is in an open state, and the hydraulic medium in the reflux medium cavity 12 enters the hydraulic medium source through the first switch unit 461, the first cavity 43 and the second switch unit 462.

[0073] When the first control valve 1 has a plurality of the reflux medium cavities 12:

[0074] The negative pressure generating device 4 is preferably configured as a cylinder piston mechanism, the cylinder piston mechanism comprising a cylinder 41 and a piston 42, the piston 42 and the cylinder 41 forming a first volume chamber 43 and a second volume chamber 47 with variable volumes, the cylinder 41 is provided with a first medium inlet 44 and a first medium outlet 45 communicating with the first volume chamber 43, and a second medium inlet 48 and a second medium outlet 49 communicating with the second volume chamber 47; each of the part of the reflux medium volume chambers 12 is communicated with the first volume chamber 43 via the reflux medium discharge channel 16 and the first medium inlet 44, and each of the remaining part of the reflux medium volume chambers 12 is communicated with the second volume chamber 47 via the reflux medium discharge channel 16 and the second medium inlet 48, and a first switch unit 461 is provided on each of the reflux medium discharge channels 16 to communicate with the first volume chamber The reflux medium chamber 12 connected to the first medium outlet 45 is connected to at least one of the reflux medium chambers 12 connected to the second medium chamber 47 via the third switch unit 40; a second switch unit 462 is respectively arranged on the fluid channel at or downstream of the first medium outlet 45 and the fluid channel at or downstream of the second medium outlet 49; when the pressure difference in the reflux medium chamber 12 connected to the third switch unit 40 is below the set value, the third switch unit 40 is in the off state, and when the pressure difference in the reflux medium chamber 12 connected to the third switch unit 40 is above the set value, the third switch unit 40 is in the on state, so as to ensure that the pressure difference in the reflux medium chamber 12 connected to the third switch unit 40 is basically constant, so as to avoid excessive vacuum in a certain reflux medium chamber 12 or excessive pressure in a certain reflux medium chamber 12 causing cavitation explosion. In the specific working process, when the hydraulic medium flowing into the reflux medium chamber 12 undergoes gas-liquid separation and expansion, and the pressure difference between the two reflux medium chambers 12 is greater than the opening pressure of the third switch unit 40, the third switch unit 40 is in the on state to release the pressure energy, thereby reducing the impact caused by the gas-liquid separation, so that the fluid in the fluid pipeline connected to the reflux medium chamber 12 can more easily flow back to the reflux medium chamber 12;

[0075] The fluid control device can work more stably. When the cylinder piston mechanism stops working, when the pressure of the hydraulic medium in the reflux medium chamber 12 is greater than the pressure in the first chamber 43 to a set value, the first switch unit 461 is in an open state, and the hydraulic medium in the reflux medium chamber 12 enters the first chamber 43 through the first switch unit 461. When the pressure of the hydraulic medium in the first chamber 43 is greater than the pressure of the hydraulic medium source 6 to a set value, the second switch unit 462 is in an open state, and the hydraulic medium in the reflux medium chamber 12 enters the hydraulic medium source in the booster tank 86 through the first switch unit 461, the first chamber 43 and the second switch unit 462.

[0076] During the reciprocating motion of the piston 42, the cylinder-piston mechanism can continuously suck the hydraulic medium in the reflux medium chamber 12 in the working state of the flow path into the first chamber 43 and the second chamber 47; in specific implementation, the first switch unit 461 can be further selectively set as an electric control valve or a one-way valve, preferably a one-way valve; as a convertible embodiment, in specific implementation, the third switch unit 40 can be further selectively set as an electric control valve. It should be noted that in order to avoid confusion, the applicant defines the switch units set on the reflux medium discharge channel 16 as first switch units 461, and the number of first switch units 461 should be selectively matched and set according to the number of reflux medium chambers 12 included in the fluid control device, and one first switch unit 461 can be selectively set on the reflux medium discharge channel 16 of each reflux medium chamber 12.

[0077] As a preferred embodiment of the present application, all the embodiments, examples and their alternative embodiments, examples containing the third switch unit 40 in the present application can further selectively enable the cylinder piston mechanism to be driven by a reciprocating drive mechanism to enable the piston to reciprocate in the cylinder body, such as Figure 6As shown, the third switch unit 40 includes a first one-way switch 401 and a second one-way switch 402 arranged in parallel, and the connection direction of the first one-way switch 401 is opposite to the connection direction of the second one-way switch 402. When the piston reciprocates, the first one-way switch 401 and the second one-way switch 402 are selectively opened, so that during the reciprocating movement of the piston of the cylinder piston mechanism, the first volume chamber 43 and the second volume chamber 47 can obtain hydraulic medium from the reflux medium volume chamber 12 connected thereto or avoid the problem of excessive difference in vacuum between the reflux medium volume chambers 12. In specific implementation, preferably, the first unit The one-way switch 401 and the second one-way switch 402 are set as one-way valves with a set opening pressure; as a convertible embodiment, the present application can also selectively enable the cylinder piston mechanism to be driven by a reciprocating drive mechanism to enable the piston to reciprocate in the cylinder body, and the third switch unit 40 is set as a controlled switch. When the piston reciprocates, the controlled switch is selectively opened so that during the reciprocating motion of the piston of the cylinder piston mechanism, the first chamber 43 and the second chamber 47 can obtain hydraulic medium from the reflux medium chamber 12 connected thereto and can keep the vacuum degree in the reflux medium chamber 12 connected thereto within a set range. In a specific implementation, the reciprocating drive mechanism is configured as a drive mechanism including a gear and a rack. The gear is driven by a drive motor or a hydraulic motor 72 and rotates back and forth, and the rack reciprocates under the drive of the gear. In a specific implementation, the reciprocating drive mechanism is limited by the vacuum degree in the first cavity 43 and the second cavity 47. When the vacuum degree in the first cavity 43 and the second cavity 47 is greater than a set value, the drive motor or hydraulic motor 72 of the reciprocating drive mechanism stops working.

[0078] As a preferred embodiment of the present application, all the above embodiments of the present application can further selectively make the first control valve 1 also include an energy storage unit 19, the energy storage unit 19 is connected to the supply medium chamber 11 so that the supply medium chamber 11 is in a set pressure range, the supply medium chamber 11 and the return medium chamber 12 in the same flow path are connected through a one-way control switch with a set opening pressure, and when the pressure in the supply medium chamber 11 is greater than the set opening pressure, the supply medium chamber 11 and the return medium chamber 12 are in a connected state. As a convertible embodiment, the one-way switch can also be selectively replaced by an electromagnetic proportional overflow valve with an adjustable opening pressure to meet the needs of intelligent control and regulation of safe opening pressure. By setting the energy storage unit 19, the present application can make the supply medium chamber 11 in a set pressure range, thereby making the fluid circuit more stable during operation; in addition, the present application can also achieve the same technical effect by setting the one-way control switch. In specific implementation, the one-way control switch can be selectively set as a one-way valve.

[0079] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application and their convertible embodiments can further selectively select to set the supply medium chamber 11 as an ellipsoidal chamber or a spherical chamber; and / or, selectively set the return medium chamber 12 as an ellipsoidal chamber or a spherical chamber. The present application improves the mechanical properties of the valve body by setting the supply medium chamber 11 and / or the return medium chamber 12 as an ellipsoidal chamber or a spherical chamber, so that the control valve can meet the requirements of high-pressure working conditions. In a specific implementation, when the flow medium chamber 11 is set as an ellipsoidal chamber, it is further preferred that the connection interface between the energy storage unit 19 and the flow medium chamber 11 is arranged inside the valve body cavity facing the focus of the central cross-section ellipse of the flow medium chamber 11; when the flow medium chamber 11 is set as a spherical chamber, it is preferred that the connection interface between the energy storage unit 19 and the flow medium chamber 11 is arranged at the valve body facing the center of the sphere of the flow medium chamber 11, so that the pressure pulsation of the pumping unit is absorbed more quickly by the energy storage unit 19, thereby ensuring that the pressure in the flow medium chamber 11 is basically stable. On the other hand, the supply medium chamber 11 and / or the return medium chamber 12 is set as an ellipsoidal chamber or a spherical chamber, and the reflection or interference of the wave between the spherical surfaces is used to reduce the hydraulic shock caused by the rapid on and off of the supply medium on-off control switch 17 or the pulsation shock caused by the hydraulic pulsation caused by the pumping unit 3 on the system, so that the supply medium chamber 11 can maintain a relatively stable working pressure, so as to better meet the requirements of the pulse flow rate that quickly provides stable pressure. The return medium chamber 12 is set as an ellipsoidal chamber or a spherical chamber, and the reflection or interference of the wave between the spherical surfaces is used to reduce the explosion shock caused by the precipitation of bubbles in the liquid medium in the return medium chamber 12 caused by the negative pressure generating device 4, thereby reducing the impact of cavitation.

[0080] As a preferred embodiment of the present application, all the above embodiments of the present invention and their convertible embodiments can further selectively set the second control valve 2 as a reversing valve. When the second control valve 2 is set as a reversing valve, the outlet end of the supply medium discharge channel 14 is connected to the first load port 81 of a hydraulic actuator 7 through the reversing valve, and the second load port 82 of the same hydraulic actuator 7 is connected to the inlet end of the return medium inlet channel 15 through the same reversing valve. One reversing valve is correspondingly set for one hydraulic actuator 7. As a convertible embodiment, the second control valve 2 can also selectively include two second valve bodies 20 (such as Figure 1 , Figure 2 and Fig.10As shown), one of the second valve bodies 20 is connected to a load port of a hydraulic actuator 7, and another of the second valve bodies 20 is connected to another load port of the hydraulic actuator 7, each of the second valve bodies 20 is provided with a first fluid channel 24, a second fluid channel 25 and a third fluid channel 26, and the second valve body 20 is also provided with a first control switch 21 for controlling the on-off of the first fluid channel 24, a second control switch 22 for controlling the on-off of the second fluid channel 25 and a third control switch 23 for controlling the on-off of the third fluid channel 26; when one of the first fluid channel 24, the second fluid channel 25 and the third fluid channel 26 is in an on state, the other two are in an off state; in specific operation, when the first fluid channel 24 is in an on state, the second control valve 2 is in a working state of supplying fluid medium to the hydraulic actuator 7; when the second fluid channel 25 is in an on state, the second control valve 2 is in a working state of refluxing the fluid medium; when the third fluid channel 26 is in an on state, the second control valve 2 is in a working state of replenishing fluid medium to the hydraulic actuator 7. In a specific implementation, when the first fluid channel 24 and the second fluid channel 25 are switched to each other, and when the third fluid channel 26 is also in a connected state, the second control valve 2 can also be selectively put into a working state to supplement the fluid medium for the hydraulic actuator 7. In a specific implementation, the second control valve 2 includes two Figure 8 The control valve shown in Figure 7 In the specific implementation, the seventh control switch 284 (specifically, Fig.10 As shown), the seventh control switch 284 can be selectively set on the valve body of the second control valve 2, or set on the flow path connected to the second control valve 2.

[0081] As a preferred embodiment of the present application, when the second control valve 2 includes two second valve bodies 20, the first control switch 21, the second control switch 22 and the third control switch 23 are further selectively driven by different driving devices, and each driving device is controlled by the electric control system so that the first control switch 21, the second control switch 22 and the third control switch 23 can each be independently opened or closed. As a convertible embodiment, specifically as Figure 8As shown, the first control switch 21 may selectively include a first rotor valve core having a first fluid channel 24, the second control switch 22 may include a second rotor valve core having a second fluid channel 25, the third control switch 23 may include a third rotor valve core having a third fluid channel 26, a valve core cavity adapted to the first rotor valve core, the second rotor valve core and the third rotor valve core is provided in the second valve body 20, the first rotor valve core, the second rotor valve core and the third rotor valve core are coaxially arranged and driven by the same driving device 285, the driving device 285 is connected to the electric control system and controlled by the electric control system, and the driving device 285 controls the opening state or the closing state of the first control switch 21, the second control switch 22 and the third control switch 23. In specific implementation, the driving device 285 may further selectively be set as a servo motor or a stepping motor.

[0082] In a specific implementation, the first control switch 21, the second control switch 22 and the third control switch 23 are further selectively set independently, and the first control switch 21, the second control switch 22 and the third control switch 23 are respectively driven by a driving device 285; as a convertible implementation, at least two of the first control switch 21, the second control switch 22 and the third control switch 23 can also be selectively set in association with each other and driven by the driving device 285; preferably, the first control switch 21, the second control switch 22 and the third control switch 23 are all set in association with each other, and the opening and closing of the first control switch 21, the second control switch 22 and the third control switch 23 are driven by the same driving device 285. In a specific implementation, during specific operation, the first fluid channel 24, the second fluid channel 25 and the third fluid channel 26 can be in a closed state at the same time under the action of the first control switch 21, the second control switch 22 and the third control switch 23. The present application enables the control valve to include three fluid channels, and each fluid channel is controlled by a control switch, so that the flow of the hydraulic medium of the same hydraulic actuator is controlled respectively by two control valves, and the two control valves can be independently controlled while realizing the function of the reversing valve.

[0083] In a specific implementation, the flow channel on the first rotating body 211 is further selectively set to be the first through hole 212 that penetrates the side wall of the valve core 27, the flow channel on the second rotating body 221 is set to be the second through hole 222 that penetrates the side wall of the valve core 27, and the flow channel on the third rotating body 231 is set to be the third through hole 232 that penetrates the side wall of the valve core 27; the angle between the axis of the first through hole 212, the axis of the second through hole 222 and the axis of the third through hole 232 projected on one end of the valve core 27 is in the range of 55° to 65°; and it is further preferred that the angle between the axis of the first through hole 212, the axis of the second through hole 222 and the axis of the third through hole 232 projected on one end of the valve core 27 is 60° (such as Fig. 9 In a specific implementation, in order to enable the driving device to provide a sufficiently large torque, the valve core 27 can be driven to rotate by further selectively selecting the driving motor with a larger driving power or allowing the driving motor to drive the valve core 27 through a reducer with a suitable transmission ratio.

[0084] As a preferred embodiment of the present application, the present application can further selectively make the control valve have a fourth control switch 281 on the second fluid channel 25 on the downstream side of the second control switch 22, and when the control valve is in the working state of fluid medium reflux, the fourth control switch 281 is in an open state; and a fifth control switch 282 is provided on the third fluid channel 26 on the upstream side of the third control switch 23, and when the control valve is in the working state of replenishing fluid medium for the hydraulic actuator, the fifth control switch 282 is in an open state. In specific implementation, the fourth control switch 281 is further selectively set as a controlled switch or the fourth control switch 281 is set as a one-way valve, and when the second fluid channel 25 is in the connected state, the fourth control switch 281 is in the open state. In specific implementation, the fifth control switch 282 can also be further selectively set as a controlled switch or the fifth control switch 282 is set as a one-way valve, and when the third fluid channel 26 is in the connected state, the fifth control switch 282 is in the open state.

[0085] As a preferred embodiment under this embodiment, all embodiments of the present application containing the fifth control switch 282 can further selectively make the third fluid channel 26 on the upstream side of the fifth control switch 282 communicate with the first fluid channel 24 on the upstream side of the first control switch 21 through the sixth control switch 283. When the control valve is in a working state of supplying fluid medium to the hydraulic actuator and the hydraulic actuator needs to be replenished with oil, the sixth control switch 283 is in an open state; for example, when the hydraulic actuator is supplied with fluid medium and the hydraulic actuator is driven by a load during operation, the sixth control switch 283 is in an open state to replenish the fluid medium to the hydraulic actuator. In the specific implementation of this embodiment, the sixth control switch 283 can be further selectively set as a controlled switch or the sixth control switch 283 as a one-way valve.

[0086] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application can further selectively provide a hydraulic actuator medium pipeline interface end 286 on the valve body, and the first fluid channel 24 on the downstream side of the first control switch 21, the second fluid channel 25 on the upstream side of the second control switch 22, and the third fluid channel 26 on the downstream side of the third control switch 23 are respectively connected to the hydraulic actuator medium pipeline interface end 286. In a specific implementation, the hydraulic actuator medium pipeline interface end 286 is connected to a medium inlet and outlet port of the hydraulic actuator via a fluid pipeline.

[0087] In the present application, when all the aforementioned embodiments of the second control valve containing the third control switch 23 are implemented, when the hydraulic actuator connected thereto is in the switching process, the third fluid channel of the load rib that is about to obtain the fluid medium is first connected to the hydraulic medium source, and then the hydraulic actuator is supplemented with sufficient hydraulic medium to avoid a large impact on the hydraulic actuator during the direct switching process.

[0088] It should be noted that the pumping unit 3 is not specifically limited and can be any hydraulic pump that meets the pumping requirements. Figures 11 to 14As shown, the pumping unit 3 preferably includes at least one cylinder-piston unit 31, the cylinder-piston unit 31 includes a piston cylinder 311 and a piston 312 adapted to the piston cylinder 311, one end of the piston 312 is fixedly provided with a piston rod 313, the piston rod 313 is transmission-connected to the crankshaft 32 via a connecting rod 314, and during the rotation of the crankshaft 32, the piston 312 reciprocates relative to the piston cylinder 311; a barrier body 33 is provided inside the piston cylinder 311 and is tightly connected to the inner circumference of the piston cylinder 311, and one end of the piston rod 313 is fixedly provided with a piston rod 313, and the piston rod 313 is transmission-connected to the crankshaft 32 via a connecting rod 314, and during the rotation of the crankshaft 32, the piston 312 reciprocates relative to the piston cylinder 311; a barrier body 33 is provided inside the piston cylinder 311 and is tightly connected to the inner circumference of the piston cylinder 311, and one end of the piston rod 313 The end passes through the barrier body 33 and is connected to the connecting rod 314, and the piston 312, the piston cylinder 311 and the barrier body 33 form a medium chamber with variable volume; the pumping unit 3 also includes a medium inlet channel 35 and a medium outlet channel 36 connected to the medium chamber 34; during operation, the hydraulic medium provided by the medium source 37 can enter the medium chamber 34 through the medium inlet channel 35, and during the movement of the piston 312 toward the barrier body 33, at least part of the hydraulic medium in the medium chamber 34 is discharged from the medium outlet channel 36.

[0089] In the specific implementation, in this application, the cylinder piston unit 31 is not specifically limited, and can be selectively set with reference to the hydraulic cylinder 71 and the cylinder piston unit of the piston engine. The barrier body 33 in this application is also not specifically limited, and can be any structure that can form a medium chamber 34 with a variable volume with the piston and the piston cylinder 311. In the specific implementation, the barrier body 33 can be selectively fixedly connected or integrated with the inner wall of the piston cylinder 311. In the specific implementation, it is preferred that the piston rod 313 and the barrier body 33 are in a relatively slidable sealed state.

[0090] As a convertible embodiment, the medium source 37 is not specifically limited, and it can be any component, unit or system that can provide hydraulic medium. In the specific implementation, it is preferred that the medium source 37 is set as an oil storage structure with a certain accommodating cavity, such as an oil tank, etc. It should be noted that the hydraulic medium stored in the oil tank is not limited to hydraulic oil. The present application drives the piston of the cylinder piston unit 31 to reciprocate at high speed in the piston cylinder 311 during the rotation of the crankshaft 32 by connecting the piston of the cylinder piston unit 31 through the connecting rod 314, thereby overcoming the disadvantage that the existing pumping unit 3 is difficult to achieve high-speed operation; the medium chamber 34 with variable volume formed by the piston, piston cylinder 311 and barrier 33 included in the pumping unit 3 of the present application can pump the internal hydraulic medium entering the medium chamber 34 to a specified position during the reciprocating motion of the piston, for example, pumping the hydraulic medium to a hydraulic actuator or a certain position. In addition, the pumping unit 3 described in the present application is composed of the existing technical means related to the cylinder piston unit 31 and the crankshaft 32, so that the design and implementation of the pumping unit 3 have a solid theoretical basis and practical experience, and thus a simple and efficient pumping unit 3 can be produced; for example, the pumping unit 3 can selectively include one cylinder piston unit 31 with reference to a single-cylinder engine, or the pumping unit 3 can include multiple cylinder piston units 31, and specifically, the pumping unit 3 can selectively include two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen or sixteen or more cylinder piston units 31. When the pumping unit 3 includes multiple cylinder piston units 31, the cylinder piston units 31 can be arranged with reference to the arrangement of a multi-cylinder piston engine, for example, multiple cylinder piston units 31 are arranged in an in-line arrangement, a V-shaped arrangement, a W-shaped arrangement or a horizontally opposed arrangement. In addition, the present application can refer to the arrangement between the cylinder piston unit and the crankshaft 32 of the existing engine to match the cylinder piston unit 31 with the crankshaft 32, thereby making the structural form of the pumping unit 3 more modular and diversified. In addition, the present application can provide a plurality of the cylinder piston units 31 and associate the plurality of the cylinder piston units 31 with the same crankshaft 32, thereby enabling the pumping unit 3 to provide a more stable hydraulic medium to the hydraulic actuator more continuously and enable the power source 5 to be in a more stable working condition; in addition, the plurality of the cylinder piston units 31 can also be provided to provide hydraulic medium to different hydraulic actuators.

[0091] It is worth noting that since the present application utilizes the cylinder piston unit 31 to realize the function of pumping hydraulic medium, in specific implementation, a gap can be selectively set between the piston and the piston cylinder 311, and the flow saturation characteristic of the gap leakage under the action of high speed and high pressure difference can be utilized to reduce the friction between the piston and the piston cylinder 311 while playing the role of pump chamber pressure unloading; thereby, energy loss caused by wear and other problems can be avoided. In specific implementation, the piston can be further selectively set as a partial cone structure, and the pressure accumulated by the gap leakage can be utilized to ensure the automatic centering of the piston; and by setting a reasonable gap, the maximum pressure difference is maintained at a certain value to protect the pressure of the medium chamber 34 from exceeding the safety pressure.

[0092] As a preferred embodiment of the present application, the medium inlet channel 35 is further selectively located at one side of the medium chamber 34, and the medium inlet channel 35 is connected to the medium source 37; during the reciprocating motion of the piston, the medium inlet channel 35 has a first working state in which the medium inlet channel 35 is connected to the medium chamber 34, and a second working state in which the medium inlet channel 35 is isolated from the medium chamber 34. As a convertible embodiment, the medium inlet channel 35 can also be selectively located in the medium source 37. In specific implementation, the medium inlet channel 35 can be selectively set as a fluid pipeline connected to the medium source 37 or as an oil replenishment window set at one side of the piston cylinder 311. The present application locates the medium inlet channel 35 on one side of the medium containing cavity 34, and further selectively connects the medium inlet channel 35 with the medium source 37 or locates the medium inlet channel 35 in the medium source 37, so that the medium containing cavity 34 and the medium source 37 are in a connected state or an isolated state during the reciprocating motion of the piston, thereby effectively simplifying the structure of the pumping unit 3 and reducing the production cost.

[0093] As a preferred embodiment of the present embodiment, the medium inlet channel 35 is further selectively located on the piston cylinder 311 on one side of the medium containing cavity 34, and the portion of the piston cylinder 311 provided with the medium inlet channel 35 is located in the medium source 37; when the piston is in the first working state, the distance between the piston and the barrier body 33 is greater than the set distance, and the hydraulic medium in the medium source 37 enters the medium containing cavity 34 through the medium inlet channel 35; when the piston is in the second working state, the distance between the piston and the barrier body 33 is less than the set distance, the medium inlet channel 35 is in a closed state, and as the piston moves toward the barrier body 33, the hydraulic medium is discharged through the medium discharge channel 36. The present application makes the medium inlet channel 35 located on the piston cylinder 311 on one side of the medium chamber 34, and makes the part of the piston cylinder 311 provided with the medium inlet channel 35 located in the medium source 37, so that the pumping unit 3 can easily supply the hydraulic medium to the medium chamber 34, and can effectively overcome the influence of the viscosity of the hydraulic medium on the operation of the pumping unit 3. In specific implementation, the medium inlet channel 35 is not specifically limited, preferably, as Fig.11 and Fig.12 As shown, the medium inlet channel 35 is configured as an oil replenishment window provided at the portion of the piston cylinder 311 located in the medium source 37. Fig.14 As shown, the piston cylinder 311 is located in the medium source 37 and the connection end serves as a medium inlet channel 35 .

[0094] As a convertible embodiment, all the above-mentioned embodiments and examples of the present invention and their convertible embodiments and examples can further selectively set the position of the crankshaft 32 when the piston is at the top dead center as the starting position, so that during the process of the crankshaft 32 rotating 120°±15° from the starting position, the medium inlet channel 35 and the medium chamber 34 are in a connected state to allow the medium to enter the medium chamber 34; during the process of the crankshaft 32 continuing to rotate to the bottom dead center, the medium inlet channel 35 and the medium chamber 34 are in a closed state, and the hydraulic medium entering the medium chamber 34 is discharged from the medium discharge channel 36. It should be noted that when the medium inlet channel 35 and the medium chamber 34 are in a connected state, the angle of rotation of the crankshaft 32 from the starting position is not specifically limited, but it is preferred that the angle is set to a range of about 120°.

[0095] As a convertible embodiment, all the above embodiments and embodiments of the present invention and their convertible embodiments and embodiments can further selectively provide the piston with at least one one-way control switch 38 connecting the medium entry channel 35 and the inside of the medium chamber 34. When the piston moves in the direction away from the barrier 33, the one-way control switch 38 has an open state. In the open state, the hydraulic medium enters the medium chamber 34 through the one-way control switch 38. When the piston moves in the direction of the barrier 33, the one-way control switch 38 is in a closed state. In specific implementation, the one-way control switch 38 can be further selectively set as a one-way valve, one of which is provided on the piston to connect the medium entry channel 35 and the inside of the medium chamber 34; or, the one-way control switch 38 can be selectively set as a one-way valve, and multiple one-way valves are evenly distributed on the piston to connect the medium entry channel 35 and the inside of the medium chamber 34. The number of one-way valves can be selectively set to two, three, four, five, six or more than seven. In the present application, a one-way control switch 38 capable of connecting the medium inlet channel 35 and the medium chamber 34 is arranged on the piston. When the piston moves toward the barrier 33, Fig.13 As shown, one side of the piston located outside the medium containing chamber 34 is bound to form an oil containing chamber 30 connected to the medium inlet channel 35 with the piston cylinder 311, and the liquid medium of the medium source 37 enters the oil containing chamber 30 from the medium inlet channel 35 as the piston moves toward the barrier body 33. When the piston moves in the direction away from the barrier body 33, the one-way control switch 38 is in an open state, and the hydraulic medium in the oil containing chamber 30 enters the medium containing chamber 34 through the one-way control switch 38, so that the medium containing chamber 34 can fully obtain the hydraulic medium required for pumping, and can also effectively overcome the influence of the viscosity of the hydraulic medium on the performance of the pumping unit 3.

[0096] It is worth noting that when the piston of the pumping unit 3 of the present application moves toward the barrier 33, the hydraulic medium can be supplied to the designated position. When the piston moves away from the barrier 33, the medium chamber 34 can be replenished with oil under the action of the one-way control switch 38. It can be seen that the piston of the pumping unit 3 of the present application can achieve a seamless connection between the two processes of oil supply and pressurized oil replenishment in one reciprocating motion process, eliminating the ineffective power loss of the idle stroke, so that the pumping unit 3 of the present application has the advantage of high pumping efficiency. In addition, in the specific implementation, the rod side of the piston can be further connected with the medium inlet channel 35 in the process of moving away from the barrier 33, so that the pumping unit 3 can more effectively overcome the defect of poor suction performance of the traditional pumping unit 3.

[0097] When all the above embodiments of the present application and their convertible embodiments are implemented, the medium source 37 can be further selectively set as a box or shell that can accommodate hydraulic medium, or the medium source 37 can be selectively set as a box or shell connected to a unit that supplies hydraulic medium from the outside. When the one-way control switch 38 is included, it is preferred that the one-way control switch 38 is set as a one-way valve. During the movement of the piston toward the barrier 33, a pressure difference is formed on both sides of the piston, which can not only automatically open the one-way valve on the piston, but also fully compress the fluid in the medium source 37, ensuring that the medium in the oil containing chamber 30 can fully flow into the medium containing chamber 34.

[0098] When the medium source 37 is configured as a box or a housing connected to a unit for supplying hydraulic medium from the outside, a stop valve can be further selectively provided between the box or the housing and the unit for supplying hydraulic medium, and when the stop valve is preferably configured as a one-way valve, the unit for supplying hydraulic medium can supply hydraulic medium to the box or the housing through the one-way valve; when the piston moves toward the barrier body 33, the unit for supplying hydraulic medium from the outside can also replenish the hydraulic medium to the box or the housing; when the piston moves away from the barrier body 33, the stop valve connected to the unit for supplying hydraulic medium from the outside can also be in a stop state, so that the box or the housing is relatively closed, and the piston pressurizes and stores energy for the hydraulic medium in the box or the housing, so that the hydraulic medium has more kinetic energy when entering the medium inlet channel 35; if the hydraulic medium is configured as hydraulic oil, the piston (towards the high-pressure side of the barrier body 33) squeezes out a part of the liquid part that is insufficiently poured in due to high viscosity through the medium inlet channel 35, and the remaining part is fully integrated, so as to facilitate uniform and high-speed pressurization.

[0099] The present application sets the one-way control switch 38 as a one-way valve, thereby improving the suction performance of the pumping unit 3 and enabling the pumping unit 3 to effectively avoid the problem of vacuuming, thereby making the operation of the pumping unit 3 more intelligent, stable and efficient, and also effectively avoiding the pumping unit 3 from causing impact on the prime mover (engine, motor, etc.), thereby increasing the service life of the pumping system.

[0100] As convertible embodiments, all the aforementioned embodiments and examples of the present invention and their convertible embodiments and examples can further selectively be selected to make the pumping unit 3 include multiple cylinder piston units 31, and the medium inlet channel 35 of each cylinder piston unit 31 is connected to the same medium source 37; or, selectively make the pumping unit 3 include multiple cylinder piston units 31, and the medium inlet channel 35 of each cylinder piston unit 31 is connected to different medium sources 37 respectively, and different medium sources 37 are isolated from each other or at least two medium sources 37 are in a connected state; or, selectively make the pumping unit 3 include multiple cylinder piston units, and part of the medium inlet channels 35 of the multiple cylinder piston units 31 are connected to the same medium source 37.

[0101] As convertible embodiments, all the aforementioned embodiments and examples of the present invention and their convertible embodiments and examples can further selectively select to make the medium discharge channel 36 of each cylinder piston unit 31 independently set; or, selectively make the medium discharge channels 36 of at least two of the multiple cylinder piston units 31 connected through a one-way control unit, and when the medium in the medium cavity 34 is discharged, the one-way control unit is in an open state; the purpose of setting the one-way control unit is to avoid cavity cross-talk between the cylinder piston units 31, thereby affecting the normal operation of the pumping unit 3.

[0102] As a convertible embodiment, all the above-mentioned embodiments, examples and convertible embodiments, examples of the present invention can further selectively select that the pumping unit 3 includes three cylinder-piston units 31, the crankshaft 32 includes three connecting rod journals, each of the connecting rod journals is connected to the piston of one of the cylinder-piston units 31 via a connecting rod, and the projection of the connecting rod journal on the end face of the crankshaft 32 is staggered at an angle of 120°±15°. The present application enables the pumping unit 3 to include three cylinder-piston units 31, and respectively to be linked with one of the three connecting rod journals staggered on the crankshaft 32, so that the projection of the three connecting rod journals on the end face of the crankshaft 32 is staggered at an angle of 120°, thereby enabling the pumping unit 3 to achieve a better working state. In a specific implementation, it is also preferred that the pumping unit 3 includes six cylinder-piston units 31, and the projections of the six connecting rod journals on the end surface of the crankshaft 32 are staggered at an angle of 60°, and the hydraulic medium supply interval of each cylinder-piston unit 31 is within the range of 60°.

[0103] As a convertible embodiment, all the above-mentioned embodiments and examples of the present invention and their convertible embodiments and examples can further selectively select to provide a pressure regulating control switch 39 on the medium discharge channel 36. When the internal pressure of the medium chamber 34 is less than the set value, the pressure regulating control switch 39 is in the off state, and when the internal pressure of the medium chamber 34 reaches the set value, the pressure regulating control switch 39 is in the open state. Under the action of the pressure regulating control switch 39, a hydraulic medium with a set pressure can be directly provided. In a specific implementation, the pressure regulating control switch 39 can be selectively set as a one-way valve with a set opening pressure.

[0104] As a preferred embodiment of the present application, all the aforementioned embodiments of the present application can further selectively enable the electronic control system to include an intelligent control module and a sensor group, wherein the sensor group includes a plurality of sensor units for detecting parameter information of the pumping unit 3, the first control valve 1, the second control valve 2 and the hydraulic actuator, and the plurality of sensor units are connected to the electronic control system intelligent control module to provide monitoring information for the electronic control system;

[0105] When working, the intelligent control module obtains the detection information of the pumping unit 3, the first control valve 1, the second control valve 2 and the hydraulic actuator from the sensor group and makes a judgment, and then controls the power source 5, the pumping unit 3, the first control valve 1 and the second control valve 2 according to the set program. When the present application is working, in order to overcome the static friction when the hydraulic actuator is started, the first control valve 1 should be kept open first, and after the relevant hydraulic actuator is started, a rapid rotation count is performed, and it is matched with the displacement sensor to perform self-adjustment of the leakage amount in the later stage.

[0106] As a preferred embodiment of the present application, in the specific implementation, the hydraulic medium used to store the hydraulic transmission system further includes a tank body, the tank body is provided with a hydraulic medium inlet and a hydraulic medium outlet, a separation device for separating impurities in the hydraulic medium is provided inside the tank body, the hydraulic medium inlet end of the separation device is connected to the hydraulic medium inlet, and the hydraulic medium separated by the separation device is used as the working medium of the hydraulic transmission system; when working, the set pressure inside the tank body is greater than the external pressure of the tank body. It should be noted that the oil tank in the present application is not limited to storing hydraulic oil, and it can be selectively set to any liquid that can be used as the hydraulic medium of the transmission system. In addition, the set pressure recorded in the present application does not make a clear requirement, and it can be specifically set according to actual needs. The present application sets a separation device capable of separating impurities in the hydraulic medium inside the oil tank body. When the hydraulic medium flows back into the oil tank, the impurities in the hydraulic medium are separated through the separation device to prepare for the next circulation. In addition, during operation, the present application makes the set pressure inside the oil tank body greater than the external pressure of the oil tank body, thereby effectively preventing dirt outside the oil tank from entering the interior of the oil tank and contaminating the hydraulic medium.

[0107] In specific implementation, all the aforementioned embodiments of the present application and their convertible embodiments can further selectively set a spiral fluid pipeline in the fluid flow circuit, thereby alleviating the fluctuation impact of the fluid medium and enabling the hydraulic control system to work more stably.

[0108] When all the aforementioned embodiments of the present application are implemented, the one-way connecting pipeline between the supply medium chamber 11 and the second control valve is further selectively set as a high-pressure medium pipeline, and the one-way connecting pipeline between the second control valve and the return medium chamber is set as a negative-pressure medium pipeline.

[0109] The present application also discloses an excavator using the aforementioned digital hydraulic intelligent control system, wherein the power source 5 is set as an engine; the hydraulic actuators of the excavator include a travel motor, a rotary motor and a plurality of variable-length telescopic cylinders; two supply medium cavities 11 and two return medium cavities 12 are arranged on the first valve body 10 of the first control valve 1; one of the supply medium cavities 11 is adapted to one of the return medium cavities 12 and serves as a component of the same flow path, and the other supply medium cavities 11 is adapted to the other return medium cavities 12 and serves as a component of the same flow path; wherein one of the supply medium cavities 11 is connected to one of the return medium cavities 12 through a supply medium discharge channel 14. The sensor group comprises: a travel motor, a rotary motor and some hydraulic actuators in a plurality of variable-length telescopic cylinders, and another flow medium chamber 11 is connected to the remaining hydraulic actuators through a flow medium discharge channel 14; the sensor group comprises: a sensor for monitoring the flow, pressure and pressure pulsation signal of the hydraulic medium inlet and the hydraulic medium outlet of the pumping unit 3, a sensor for monitoring the flow, pressure and pressure pulsation signal of at least part of the medium channel of the first control valve 1, a sensor for monitoring the flow, pressure, pressure pulsation signal and shaft end angular displacement of the load port of the hydraulic motor, and a sensor for monitoring the flow, pressure, pressure pulsation signal and telescopic end displacement of the load port of the telescopic cylinder.

[0110] In specific implementation, the power source 5 of the excavator can also be selectively set as an electric motor or a hybrid drive unit including an engine and a motor. In specific implementation, in order to further improve the intelligent control performance of the excavator, a pressure sensor can be further selectively set in the reflux medium chamber 12 connected to the negative pressure generating device 4 to monitor the negative pressure value or the air burst pressure value, to control whether the negative pressure generating device 4 stops working or speeds up the working frequency, and to assist in diagnosing the leakage of the excavator pipeline; and further selectively use a sensor for monitoring the flow, pressure, pressure pulsation signal and output shaft end angular displacement of the rotary motor load port. The drive unit and the drive device are both connected to the electric control system, and are controlled by the electric control system; in order to achieve better intelligent control, the electric control system can be further selectively made to include an intelligent control unit, and the intelligent control unit includes a chip and / or a remote control system and / or an automatic return device when power is off (for example, electromagnetic shielding is turned on, and the automatic return function is realized after electromagnetic recovery, ensuring that the valve core of the drive unit is in the off state, and the valve core of the drive device is in the state of being connected to the medium source).

[0111] In the specific working process, the intelligent control unit predicts and adjusts the overspeed of the hydraulic actuator, including the following processes:

[0112] First, the intelligent control unit obtains the position status (including the horizontal position status of the whole machine, whether the bucket at the front end of the boom is supported, etc.) based on the displacement of the mechanical actuator and / or the gravity sensor included therein;

[0113] Secondly, the position state of hydraulic actuators (such as boom cylinder, bucket cylinder, arm cylinder, and travel motor) is predicted in combination with the control program;

[0114] Thirdly, determine whether the actuator is subject to the additional effects of gravity or inertia;

[0115] Finally, the second control valve independently controlled by the load port is used to replenish oil or supply high-pressure oil to the piston chamber in the opposite direction of the gravity or inertia force exerted on the corresponding hydraulic actuator to reduce the additional effect of gravity or inertia force. Among them, the adjustment of the operating speed of the hydraulic actuator depends on the amount (number of pulses of high-pressure oil) and speed of the high-pressure oil supplied by the flow medium chamber to ensure that the operating speed of the hydraulic actuator is adjusted to a controllable range, avoid the risk of overspeed of the actuator, and ensure that the actuator is controllable.

[0116] In order to improve the self-rescue capability of the excavator, the hydraulic excavator is further selectively provided with two sets of power sources 5 and two sets of pumping units 3, and the pumping units 3 respectively supply oil to the two flow medium cavities 11 in the first valve body 10 of the first control valve 1. When one set of power sources 5 and / or pumping units 3 is damaged at the disaster site, as long as the other set of power sources 5 and pumping units 3 can supply oil to one of the two flow medium cavities 11, the electric control valve between the two flow medium cavities 11 can be opened to ensure that both of the flow medium cavities 11 have pressurized oil, thereby ensuring that the actuators provided with hydraulic power by the two flow medium cavities 11 can perform actions, which is a redundant design for disaster relief at the disaster site or self-rescue in evacuating dangerous environments.

[0117] The drawings of this application are for illustration only, and any technical solution that meets the requirements of the text of this application shall fall within the protection scope of this application.

[0118] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0119] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A digital hydraulic intelligent control system, characterized in that: It includes a power source, a hydraulic medium source, a pumping unit, a first control valve, a second control valve, a hydraulic actuator and an electronic control system; The first control valve comprises a first valve body, a supply medium chamber and a reflux medium chamber are arranged inside the first valve body, a supply medium inlet channel and a supply medium outlet channel connected to the supply medium chamber are arranged on the first valve body, and a reflux medium inlet channel and a reflux medium outlet channel connected to the reflux medium chamber are arranged on the first valve body; the first control valve further comprises a supply flow cut-off control switch and a reflux flow cut-off control switch, the supply flow cut-off control switch controls the opening and closing of the supply flow medium outlet channel, the reflux flow cut-off control switch controls the opening and closing of the reflux medium inlet channel, and the supply flow cut-off control switch and the reflux flow cut-off control switch are driven by a driving unit; The power source is arranged in transmission with the pumping unit, the hydraulic medium inlet of the pumping unit is communicated with the hydraulic medium source, and the hydraulic medium outlet of the pumping unit is communicated with the inlet end of the flow supply medium inlet channel, so as to provide hydraulic medium to the flow supply medium chamber; The outlet end of the supply medium discharge channel and the inlet end of the return medium inlet channel are respectively connected to the corresponding oil ports of the second control valve through a one-way oil circuit, and the outlet end of the return medium discharge channel is connected to the hydraulic medium source to form a working circuit; the second control valve is driven by a driving device; The second control valve is respectively connected to the first load port and the second load port fluid circuit of the hydraulic actuator, so that the second control valve can perform reversing and / or speed control on the hydraulic actuator; or, the second control valve is connected to the first load port fluid circuit of the hydraulic actuator, so that the second control valve can perform reversing and / or speed control on the hydraulic actuator; The driving unit and the driving device are both connected to the electric control system, and the driving unit and the driving device are both controlled by the electric control system; When working, the flow cut-off control switch is driven by the driving unit to keep the flow medium discharge channel in an alternating working state of being on and off, and to make the first control valve supply pulse hydraulic medium to the outside, and the driving unit controls the frequency of connecting the flow medium discharge channel; The second control valve is configured as a reversing valve; or, The second control valve comprises two second valve bodies, one of which is connected to a load port of a hydraulic actuator, and the other of which is connected to another load port of the hydraulic actuator. A first fluid channel, a second fluid channel and a third fluid channel are provided on each of the second valve bodies. A first control switch for controlling the on-off of the first fluid channel, a second control switch for controlling the on-off of the second fluid channel and a third control switch for controlling the on-off of the third fluid channel are also provided on the second valve body. When one of the first fluid channel, the second fluid channel and the third fluid channel is in an on state, the other two are in an off state. When the first fluid channel is in an on state, the second control valve is in a working state of supplying fluid medium to the hydraulic actuator. When the second fluid channel is in an on state, the second control valve is in a working state of refluxing fluid medium. When the third fluid channel is in an on state, the second control valve is in a working state of replenishing fluid medium to the hydraulic actuator. The pumping unit includes at least one cylinder-piston unit, the cylinder-piston unit includes a piston cylinder and a piston matched with the piston cylinder, one end of the piston is fixed with a piston rod, the piston rod is connected to the crankshaft through a connecting rod, and during the rotation of the crankshaft, the piston reciprocates relative to the piston cylinder; The piston cylinder is provided with a barrier body which is tightly connected to the inner circumference of the piston cylinder, one end of the piston rod passes through the barrier body and is connected to the connecting rod, and the piston, the piston cylinder and the barrier body form a medium chamber with a variable volume; the pumping unit also includes a medium inlet channel and a medium outlet channel connected to the medium chamber; During operation, the hydraulic medium provided by the medium source can enter the medium chamber unidirectionally through the medium inlet channel, and during the movement of the piston toward the barrier body, at least part of the hydraulic medium in the medium chamber is unidirectionally discharged from the medium discharge channel; The electronic control system includes an intelligent control module and a sensor group, wherein the sensor group includes a plurality of sensor units for detecting parameter information of the pumping unit, the first control valve, the second control valve and the hydraulic actuator, and the plurality of sensor units are connected to the electronic control system intelligent control module to collect and provide monitoring information for the electronic control system; During operation, the intelligent control module obtains detection information of the pumping unit, the first control valve, the second control valve and the hydraulic actuator from the sensor group and makes a judgment, and then controls the power source, the pumping unit, the first control valve and the second control valve according to the set program.

2. According to claim 1, the digital hydraulic intelligent control system is characterized in that: The first valve body of the first control valve is provided with more than two supply medium cavities and at least one return medium cavities, each supply medium cavities and one return medium cavities are adapted to be connected and serve as components of the same flow path; each supply medium cavities are respectively connected to the corresponding oil ports of the second control valve through one or more supply medium discharge channels through a one-way oil path, and the outlet end of the return medium discharge channel is connected to the hydraulic medium source through a one-way oil path to form a working circuit; and each supply medium discharge channel is provided with a supply flow cut-off control switch, and each supply flow cut-off control switch is driven by a driving unit; The driving unit is a servo motor, a stepping motor or a variable frequency motor, and / or the driving device is a servo motor or a stepping motor.

3. According to claim 2, the digital hydraulic intelligent control system is characterized in that: The digital hydraulic intelligent control system also includes a negative pressure generating device. The reflux medium chambers arranged on the first valve body of the first control valve are respectively connected to the negative pressure generating devices. When the negative pressure generating devices are in a working condition of forming negative pressure, the hydraulic medium in the reflux medium chamber connected to the negative pressure generating device is sucked out.

4. According to claim 3, the digital hydraulic intelligent control system is characterized in that: When the first control valve has a reflux medium chamber: The negative pressure generating device is configured as a cylinder-piston mechanism, the cylinder-piston mechanism comprises a cylinder and a piston, the piston and the cylinder form a first volume chamber with a variable volume, the cylinder is provided with a first medium inlet and a first medium outlet communicating with the first volume chamber; the reflux medium volume chamber is communicated with the first volume chamber via a first switch unit and the first medium inlet, and when the volume of the first volume chamber increases, the first switch unit is in an open state; during the operation of the cylinder-piston mechanism, the cylinder-piston mechanism sucks the hydraulic medium in the reflux medium volume chamber into the first volume chamber, and squeezes the hydraulic medium sucked into the first volume chamber from the first medium outlet to the hydraulic medium source; When the first control valve has a plurality of reflux medium cavities: The negative pressure generating device is configured as a cylinder-piston mechanism, the cylinder-piston mechanism comprising a cylinder and a piston, the piston and the cylinder forming a first volume chamber and a second volume chamber with variable volumes, the cylinder being provided with a first medium inlet and a first medium outlet communicating with the first volume chamber, and a second medium inlet and a second medium outlet communicating with the second volume chamber; Each of a part of the reflux medium cavities is communicated with the first cavity through a reflux medium discharge channel and a first medium inlet, and each of the remaining part of the reflux medium cavities is communicated with the second cavity through a reflux medium discharge channel and a second medium inlet, a first switch unit is provided on each of the reflux medium discharge channels, and the reflux medium cavity communicated with the first cavity is communicated with at least one of the reflux medium cavities communicated with the second cavity through a third switch unit; A second switch unit is respectively provided on the fluid channel at the first medium outlet or downstream thereof and the fluid channel at the second medium outlet or downstream thereof; When the volume of the first cavity increases, the first switch unit on the reflux medium discharge channel on the working flow path and connected to the first cavity is in an open state, and the second switch unit connected to the first cavity is in an off state; When the volume of the first cavity decreases, the first switch unit on the reflux medium discharge channel on the working flow path and connected to the first cavity is in an off state, and the second switch unit connected to the first cavity is in an on state; When the volume of the second cavity increases, the first switch unit on the reflux medium discharge channel on the working flow path and connected to the second cavity is in an open state, and the second switch unit connected to the second cavity is in an off state; When the volume of the second cavity decreases, the first switch unit on the reflux medium discharge channel on the working flow path and connected to the second cavity is in an off state, and the second switch unit connected to the second cavity is in an on state; When the pressure difference in the return medium chamber connected to the third switch unit is below the set value, the third switch unit is in the off state; when the pressure difference in the return medium chamber connected to the third switch unit is above the set value, the third switch unit is in the on state.

5. The digital hydraulic intelligent control system according to any one of claims 1 to 4, characterized in that: The first control valve further includes an energy storage unit, the energy storage unit is connected to the supply medium chamber so that the supply medium chamber is within a set pressure range, the supply medium chamber and the return medium chamber in the same flow path are connected via a one-way control switch with a set opening pressure, when the pressure in the supply medium chamber is greater than the set opening pressure, the supply medium chamber and the return medium chamber are in a connected state; or The first control valve also includes an energy storage unit, which is connected to the supply medium chamber so that the supply medium chamber is within a set pressure range. The supply medium chamber and the return medium chamber are connected via an electromagnetic proportional overflow valve with an adjustable opening pressure. When the pressure in the supply medium chamber is greater than the set opening pressure, the supply medium chamber and the return medium chamber are in a connected state.

6. The digital hydraulic intelligent control system according to claim 1 is characterized in that: When the second control valve includes the second valve body, the first control switch, the second control switch and the third control switch are driven by different driving devices, and each driving device is controlled by the electric control system so that the first control switch, the second control switch and the third control switch can each be independently opened or closed; or, When the second control valve includes the second valve body, the first control switch includes a first rotor valve core having a first fluid channel, the second control switch includes a second rotor valve core having a second fluid channel, and the third control switch includes a third rotor valve core having a third fluid channel. A valve core cavity matching the first rotor valve core, the second rotor valve core and the third rotor valve core is provided in the second valve body. The first rotor valve core, the second rotor valve core and the third rotor valve core are coaxially arranged and driven by the same driving device. The driving device is electrically connected to the electronic control system and controlled by the electronic control system. The driving device controls the opening state or the closing state of the first control switch, the second control switch and the third control switch.

7. An excavator using the digital hydraulic intelligent control system as claimed in claim 1, characterized in that: The power source is set as an engine, an electric motor, or a hybrid power drive unit including an engine and an electric motor; The hydraulic actuator of the excavator includes a travel motor, a slewing motor and a plurality of luffing and telescopic cylinders; The first valve body of the first control valve is provided with two supply medium cavities and two return medium cavities; One of the supply medium chambers is matched with one of the return medium chambers and serves as a component of the same flow path, and another of the supply medium chambers is matched with another of the return medium chambers and serves as a component of the same flow path; Among them, one of the flow medium chambers is connected to a travel motor, a rotary motor and some hydraulic actuators in a plurality of variable-length telescopic cylinders through a flow medium discharge channel, and the other flow medium chamber is connected to the remaining hydraulic actuators through a flow medium discharge channel; The sensor group includes: Sensors for monitoring the flow rate, pressure and pressure pulsation signals of the hydraulic medium inlet and the hydraulic medium outlet of the pumping unit, A sensor for monitoring the flow rate, pressure and pressure pulsation signal of at least part of the medium channel of the first control valve, Sensors used to monitor the flow, pressure, pressure pulsation signal and shaft end angular displacement of the load port of the hydraulic motor. Sensor used to monitor the flow, pressure, pressure pulsation signal and telescopic end displacement of the telescopic cylinder's load port.

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